Device for actuating the thread guide of flat knitting machines



Aug. 25, 1936. K. R. LIEB ERK NECHT ,9

DEVICE FOR ACTUATING THE THREAD GUIDE OF FLAT KNITTING MACHINES Filed Dec. 13, 1934 iztarny Patented Aug. 25, 1936 DEVICE FOR ACTUATIING THE THREAD GUIDE 0F FLAT KNITTING MACHINES Karl Richard Lieberkne'cht, Oberlangwitz,

Ger-ma Application In 6 Claims.

The present invention relates to a device for actuating the thread guide.v of a fiat. knitting machine in which the lead of the thread guide with respect to the sinkers advanced by the slur cock remains constant even during narrowing.

Arrangements are already known for attaining a constant lead of the thread guide. In a very simple construction two friction elements are located on either side of and drive a sliding element engaging the thread guide. These friction elements however engage the sliding element somewhat harshly.

For avoiding the shocks an arrangement has been proposed in which a specially guided steel band, chain or the like secured at both ends to the guide bar for the slur cock occasions the temporary coupling of guide bar for the slur. cock and thread guide. This arrangement however is unreliable as due to the varying load the steel band (chain. or the like) or the elements moved thereby are liable to break.

Moreover a disadvantage arises in that the steel band connected with the guide bar for the slur cock is directed over rollers so that the motion of the thread guide is initiated and terminated in accordance with a sine law and not with uniform acceleration or deceleration.

Furthermore arrangements are known in which the friction elements are opened and closed electrically or by means of slide links but the con struction is inconvenient because each individual friction element must be controlled,

In contradistinction thereto and according to the invention an intermediate memberwhich is thread guide and actuated by the drive of the which has a supplementary motion imparted to it as desired by adjustable guides, moves in ,the shaped cam groove 01. a guide member connected with the thread guides or with the thread guide bar and thereby throws said guide member into or out of motion with an acceleration or deceleration corresponding to the configuration of the cam groove.

The shaped cam groove so that the throwing into or out or motion of the guide member or of the thread .guides or thread guide bar connected therewith is eiiected with constant acceleration or deceleration.

Cam guides as such are already known in flat knitting machines. They ing devices and merely damp the impact of the thread guide bars against their end abutment. Consequently these devices do not couple together at any desired time a driving element and a driven element so that it is not possible to solve is preferably parabolic serve as shock absorb- December 13, 1934, Serial No. 757.393 Germany December 14, 1933 (C1. (SS-J26) therewith the problem in the case of a constant travel of the driving element of delimiting without jarring and without additional power consumption a varying path oi the driven element traversed at the constant speed of the driving member, in such manner element has traversed the desired path no more power istaken from the driving element for the driven element.

One embodiment of shown bywayof example in the accompanying drawing, in which:

Fig. 1 shows a side view of the guides conthat after the driven' the present invention is 0 trolled by the narrowing mechanism and of the 15 elements controlled by the guides,

Fig. 2 a plan view of Fig. 1,

Fig. 3 the construction of the parabolic guide for the member to be actuated,

Fig. 4 shows the actual parabolic guide,

Fig. 5 shows the general arrangement 0! the thread guide drive,

- Figi 6 shows a stocking blank,

Figs. 7 and 8 are side views showing separately the guide plates of Figs. 1, 2 and 5.

Carried on the arm a constant path is a pitman 2 the end of which carries a pin 3 with roller l. The roller 4 is guided in the slot 5 defined by the guide plates 6 and 1.

When moving from the left for example the roller 4 first traverses the lower rectilinear section 511. At the section 5b oi. the guides it has imparted-to it smoothly an auxiliary movement in the upward direction inadditlon to its motion to the right. Along the section 50 it again traverses a rectilinear path and then at Ed has a further supplementary motion in the upward direction and finally traverses the rectilinear section 5c of the guides up to the point where its motion is reversed. r

Attached to each of the guide plates Q and I is a link 8 and 9 whereby a relative displacement Behindthe guide plates 6 and I at the level of the section be is the thread guide rod Ill which slides in bearings, not shown. Arranged on this rod I0 is a guide member II with a cam groove I! in which the roller l3 carried at the end of the pitman I opposite the roller I is adapted to engage.

The cam groove I! in the. guide member ll consists of a partially parabolic curve which extends as indicated in Fig. 3. From a-b the cam groove is rectilinear and at an inclination corresponding to that of the section 5b 0! the guides I which reciprocates over,

by a parabolic section bc which runs into a vertical section cd. Thereupon the cam groove turns in the other direction along the parabolic section d-e and terminates in a rectilinear section e] the inclination of which corresponds to that of the section 5d of the guides sand I. The broken lines in Fig. 3 show the combinations of the parabolic curves.

During the motion of the pitman 2 from left to right the rod I 0 remains stationary until the roller 4 has traversed the rectilinear section 5a and a part of the section 5b of the guide plates 6 and I and the roller I3 after engagement in the cam groove I2 has reached the parabolic portion thereof. At that moment the rod I 0 is gradually accelerated.

When the roller I3 has reached the apex c of the parabola then full speed. This is equal to the speed of the reciprocating arm. Then with reduced speed the roller I3 rises in the rectilinear section c-d up to the central point M and displaces the rod III to the right at full speed, the end of the pitman 2 being guided in the section 50 of the guides 6 and I. When the roller 4 enters the. guide section 5d the roller I3 is again accelerated in its auxiliary motion from the central point M up to the apex d of the second parabola. When the roller I3 enters the parabolic portion I2de then the rod I0 commences to be decelerated until it is brought to rest at I 2e. Due to the guide section 5c the roller l3 continues to rise along the rectilinear path e-f andleaves the guide member I2 at f, the guide member remaining stationary at 5d. The motion of the pitman 2 is completed in the guide section 5e. On the return stroke of the arm I from right to left the operations described above are carried out in the reverse manner. The acceleration of the rod I II at the commencement of its motion and its deceleration when brought to rest is determined by the parameter of the parabola.

Fig. 5 shows the incorporation of this device in a flat knitting machine.

In the embodiment shown in the drawing the device according to the invention is driven from theknown coulier mechanism. The draw cam I4 runs between two rollers I5 provided on the actuating bar. The latter is pivotally connected with the arm I6 and the draw lever I and drives the latter to and fro. By way of the link II the arm I engages the guide bar for the slur cock I8 on which are carried the slur cocks, not shown, for actuating the sinkers. slur cock I8 is moved at a speed determined by the draw cam I4. From the arm I the pitman 2 also leads to the device tion the rod l0 of which is in this case constructed as thread guide actuating bar. The two links 8 and 9 are controlled from the narrowing mechanism (not shown) of the flat knitting machine so that the length of the section 5c of the guides 6 and I and thus the path s traversed by the thread guide actuating bar I0 is adjusted in accordance with the width of the fabric to be worked.

The mode of operation ofthe arrangement according to the invention is as follows:

In the case of fabric of different width. for example in the case of legs of stockings as shown in Fig. 6, the sinkers always sink over the entire width of the section of the fiat knitting machine, i. e., thev slur cock path remains constant although the width of the fabric varies. The path 2,051,955 6 and I. This rectilinear section a b is followed the rod III has attained its.

The guide bar for the according to the inventraversed by thread of the fabric.

For this purpose the intermediate member is moved by the thread guide drive over a constant path with the same speed as the guide bar for the slur cock. The auxiliary motion of the intermediguide varies with the width ate member which is effected in a direction at right angles to the main motion under the control of the guides eiiects the intermittent actuation of the thread guide bar. By altering the position of the guides in accordance with the working width from g to 9' (Fig. 6) the path of the thread guide bar also varies and the thread guide is thrown into and out of motion smoothly with a uniform consumption of power in consequence of the parabola configuration of the cams. In this way the problem of moving the thread guide over the working section with the same speed and at the same separation from the slur cock in spite of the variable working path of the thread guide is attained in a manner which is far superior to the arrangements hitherto known for solving this problem.

' I claim:

1. In a flat knitting machine a mechanism for actuating the thread guide devicecomprising a driving member, an intermediate member driven thereby, a guide member adapted to transmit the drive to said thread guide device, a cam groove in said guide member and adjustable guides for bringing said intermediate member into and out of engagement with said cam groove whereby the desired motion is imparted to the thread guide device with an initial acceleration and flnai deceleration determined by the configuration of said cam groove.

2. In a flat knitting machine a mechanism for actuating the thread guide device comprising a driving member, an intermediate member driven thereby, a guide member attached to the-thread guide device, a cam groove in said guide member and adjustable guides for bringing said intermediate member into and out of engagement with said cam groove, whereby the desired motion is imparted to said thread guides with an initial acceleration and final deceleration determined by the configuration of said cam groove.

3. In a flat knitting machine a mechanism for actuating the thread guide device comprising a driving member, an intermediate member driven thereby, a guide member adapted to transmit the drive to said thread guide device, a cam groove in said guide member and adjustable guides for bringing said intermediate member into and out of engagement with said cam groove, parabolic sections in said cam groove for cooperation with said intermediate member during acceleration and... deceleration of said guide member by said intermediate member, whereby the desired motion is imparted to said thread guide device with constant initial acceleration and final -deceleration preceding and following the motion in synchronism with said intermediate member.

4. In a flat knitting machine a mechanism for actuating the thread guide device comprising a driving member, an intermediate member driven thereby, a guide member attached to the thread guide device, a cam groove in said guide member and adjustable guides for bringing said intermediate member into-and out of engagement with said cam groove, parabolic sections in said'cam groove for co-operation with said intermediate member during acceleration and deceleration of said guide member by said intermediate whereby the desired motion is imparted to said thread guides with constant initial acceleration and final deceleration preceding and following the motion in synchonism with said intermediate mem-' bar.

5. In a fiat knitting machine, a mechanism for actuating the thread guide device comprising a reciprocating driving member, an intermediate member linked to and thus reciprocated thereby. a pin extending through the free end of 'said intermediate member, a roller on each'end '0! said pin, slotted plates forming a guide slot of length not less than the path traversed by said intermediate member and embracing one of said rollers, two curved portions in said guide slot whereby said one roller is caused to move along an inclined path at two points during each traverse, a guide member associated with the thread guide device, and in said guide member a cam groove adapted to receive the second or said rollers during the first of said motions along an inclined path, said second roller being moved out of engagement with said cam groove during the secand of said motions along an inclined path.

6. In a flat knitting machine. a mechanism for actuating the thread guide device comprising a reciprocating driving member, an intermediate member linked to and thus reciprocated thereby, a pin extending through the free end of said intermediate member, a roller on each end of said pin, slotted plates forming a guide slot of length not less than the path traversed by said intermediate member and embracing one of the said rollers, two curved portions in said guide slot whereby 'said one roller is caused to move alonz an inclined path at two points during each traverse, means actuated from the narrowing mechanism of said machine for adjusting said slotted plates so as to vary the separation of said curved portions, a guide member associated with the thread guide device, and in said guide member a cam groove adapted to receive the second of said rollers during the first of said motions along an inclined path. said second roller being moved out 20 of engagement with said camgroove during the second of said motions along an inclined path.

KARL RICHARD IJEBERKNECHI. 

